Holy moly... the brass that the fn factory rounds produced were filthy... (I catch my brass) and boy did they stink. Serious powder stains on the mouth, and neck of the rounds. And there was visible smoke from the shots.
Accuracy was meh... but I'm worried I got a bad batch or FN is cutting corners.

Conversely the shots from my handloads were superlative and the best 5.7 I've ever shot.

Every shot I took with the hand loads went precisely where I wanted it to go. And I mean that... precisely. I was joking with my friend and said I was going to aim for and hit the nose of the target (zombie type target) we had down range, and took aim expecting it to be a bit off. Pow... right on target. It was the difference between using an axe to cut something... and a scalpel. The hand loads were supremely precise.

And here's the interesting thing.

If you use accurate #7... it's impossible to double charge your 5.7 rounds. Why you ask? Because you can't fit two charges of #7 into a 5.7x28 casing. There simply isn't room. it will overflow the case. So, so long as you measure each charge yourself... impossible to overload the case.

So if you are interested in trying your hand at 5.7x28 This is a winning combo in my opinion.

But back to the FN batch. rounds were not tightly grouped at all no matter how I tried at 30 or 40 meters. I took extra care in fact with the FN rounds. Breathing out on the shot, gentle pressure, pausing to aim, good stance. relaxed. nothing helped.

But it's the junk on the brass that bothers me. The rounds were easily able to be seen as dirtier than the rounds I loaded. This is an honest to god disgrace for FN. These are expensive rounds... I actually feel cheated by the quality they provided.

Chances are you were pushing higher pressures than FN originally intended you to. Low pressure charges generate more smoke and unburned powder. It's also possible since you were using a hotter primer this made the difference.

FN is a very innovative company, however I'm not sure every innovation they make is for the best. I think the 5.7 is a neat concept, however I personally don't like the way they implemented it, but that's neither here nor there.

I've fired 5.7 before. I know what it's supposed to smell and feel like.. .this did not feel right even if it was factory.
Also the fouling of the casings. I've never seen so much residue on a 5.7 casing after firing. Either FN is trying a new lower quality primer or have changed the powder for something that fouls more.

Here's the thing, Simple green will take off most paints and lacquers because it's a wetting agent. This is a trick that's known to most Miniature painters in the gaming world (role playing and tactical warfare gaming like warhammer 40k and such... it's the paint remover of choice for them) So the key here is not to let it sit too long and to use a highly diluted solution. If you let it sit too long... the stuff will somehow get under the coating and separate it from the casing. It'll slough off like skin in fact. It's easy to see when it's been there too long, it'll wrinkle and bubble up off the case.

Also No soap to start with, no acids like vinegar, no bases like bleach, or neutralizing agents like baking soda (which can be abrasive)

Let it sit for about 20 mins in the sg solution, then remove the brass (save the cleaning solution) and rinse in first hot, then cold water in a collindar. This will keep the solution liquid, and then dilute it and rinse it off cleanly.

Let them rest on a beach towel (big absorbant towel) and roll them to get as much water out as possible.

Then put them in reloading trays and spray with lee sizing lube mixed with denatured alcohol (a 2oz tube to a nearly full zep sprayer full of alcohol (zep sprayer you can get at home depo cheap oh and let the lube and alcohol mix stand overnight before you use it, it lets it break down better) lightly spray with lube to get it in the necks and then bag in a ziplock and spray a few spritzes in to coat them and roll them around.

Then resize and decap while still damp and lubed.

Then back into the 10 parts water to 1 part simple green for another 10 minutes. Then out... and scrub with a test tube scubber (plastic bristles) and rinse in hot and cold water again.

This should have any residue nice and soft and you can swab out the primer pockets with qtips. Let dry. Then trim necks and scrub necks only with 0000 steel wool if you heat the necks with a torch to destress the necks.

That's it.

Why the steel wool? Well If you anneal the necks you're gonna burn off that coating anyway... so you should follow that up with a good scrub to take off the residue. The coating appears to be for case ejections and loading to my eye. The neck should be non critical for the use of the round and maybe even detrimental since it might create bad seals. Otherwise the steps I gave above seem to work fine for cleaning.

hey if you wanna get rid of those ammo can's you let me know. I'm very interested in them if you wanna part with them.

As to the process. I'm overly cautious with a round initially, but I also am willing to experiment. Here's the thing about the coating. I've been researching it and from what I can tell the coating is there for the round because it was intended to be used in the fully automatic version of the p90. Therefore it needs to be able to eject in fast cycling operations. It may actually be completely superflous for the ps 90 or FiveseveN. But for now I've not tried because I don't have enough brass in that caliber to warrant me stripping 50-200 rounds of it of the coating to see what happens.

I'm betting that removing the coating will have negligible effect on the round in the civilian ps 90 if you apply a little wax or lube to the casings to impede corrosion. But if you want to donate a few hundred brass to me, I could test that theory. .

And yes, it's a picky little round. But I'm approaching it like a science experiment. using starting loads only and taking extra care throughout the process. As I get more familiar with it I'll tweak my processes and see what does and does not work. But for now, acc7 and 40 gr vmax is where I'm starting. Got 100 rnds each primed with cci, remington, and winchester small rifle and other primers to test which combo of powder and primers work best. Also I'm going to be trying Ramshots Silhouette instead of true blue after I've charted the two in excel for various rounds to see what their pressure ratios are. I've heard dang good things about silhouette and its super clean burn that makes me think it might be the optimal powder for the 5.7 but I'm going to play it safe and try to do simulations of what the burn would be like since there's no data sheet for RS for the round.

I've loaded a couple thousand 5.7 loads, some with AA#7 and True Blue. From everything I've loaded and read, True Blue is the superior powder for this cartridge. I'm sure Sihouette would be good also. It is a super fun round to reload. But.... you have to like the slow tedious process.

Most of the people I've talked to who load/have loaded the 5.7 round say once the coating goes, it's useless after that.

I think the big problem is the 5.7 is a blowback actuated round... it's also very small diameter, which means extraction is going to be difficult. (physics is working against you) hence the lubricant on the cartridge case.

I just read a bunch of posts on reloading 5.7... I hope I never have to, and now I'm even more confused as to why this cartridge/pistol was ever let out of the factory with it's present configuration.

Probably because it works really well, can pierce body armor like a knife through butter at a fraction of the size of an equally effective round, and has limited range to prevent accidental friendly casualties at range. As to the coating, I have been reading up and there is considerable debate about the coating being needed in the ps90. A lot of ppl are saying its only needed for full auto because of the high cycle rate. At lower cycles its unneeded. But I'd love to confirm it for myself

It would be interesting to see if cartridges that had the lube stripped off work, or if another lube like moly sulfide would work.

Don't get me wrong, I totally understand the veracity of the design objectives, and I think they're all well met. However from a manufacturing and maintenance perspective it seems to fall really short of where it should be.

In contrast if you look at the H&K MP7 round... the 4.5x33mm (IIRC) it has a significant cartridge taper, and I think it fires from a locked bolt. I've seen nothing about it requiring a specific lubricant being applied to the cartridge case to get it to work properly.

Actually I've heard that they work just fine in the ps90 but less so in the fiveseveN pistol. I likewise would think that something like moly shoudl do just fine... it should coat the insides and be nice and slippery.

This is part of why I'm experimenting. For starters I'm steel wooling the coating off the neck. I can see no need for it other than they coat the whole cartridge and can't avoid the next. If anything I expect I'll get a BETTER seal on the mouth by not having the coating on it... which should mean better pressures and fps.

If you want to join in the experimenting or donate something to have me try it I'd be happy to give it a whirl.

lemme dig around, I know I have a few pounds of motor mica I used to use for case neck lubrication on my match brass, and I *KNOW* around here somewhere is a 1lb powder jar full of molybdenum disulfide I just don't think I've seen it in over a year.

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